After leaving one coastal paradise, we continued south to another one: Bacalar! Home of the lagoon of seven colors (we counted five but whatever) we found ourselves in a town more developed than Mahahual, but less than Tulum. Great balance! Lots of restaurants and scenic bait for Instagram shots. Not much actual beach to speak of, but very beautiful coastline.
When we were trying to decide between visiting the expensive ruins of Uxmal or Chichenitza, we learned about a very remote ruins site just north of the Guatemalan border, where you could spend a morning without seeing more than a dozen other visitors. A place where you could hear howler monkeys, climb the ruins, and from the top see other temples peeking out of the forest. We made a note to check it out later. When we got far enough south, we drove a couple hours west from the coast to stay overnight in Xpujil, the nearest town that provided easy access (2 more hours) to the unspoiled ruins site of Calakmul. It lived up to the hype. We're sure there are more remote and less developed sites, but Calakmul offered exactly what we wanted: beautifully restored original temples with none of the crowds. Definitely our favorite ruins site in Mexico.
Upon returning to Bacalar, we did a little more sightseeing and prepared for the next leg of our journey: Belize!